<!DOCTYPE html>
<html lang='en'>

<head>
  <meta charset='UTF-8'>
  <meta http-equiv='X-UA-Compatible' content='IE=edge'>
  <meta name='viewport' content='width=device-width, initial-scale=1.0'>
  <title>Document</title>
  <script src='../vue.js'></script>
</head>

<body>
  <div id='app'>
    <h1>{{msg}}</h1>
  </div>
  <script>
    Vue.config.productionTip = false;
    const vm = new Vue({
      data: {
        msg: 'hello vue!'
      }
    })
    //把vm的挂载单独书写出来(除了我们可以自由选择挂载时机以外,和el配置项没有其他的区别)
    setTimeout(() => {
      vm.$mount('#app') //元素或者选择器
    }, 2000)

    /* //下边的写法也比较常见
    new Vue({
      data: {
        msg: "hello Vue"
      }
    }).$mount("#app") */
  </script>
</body>

</html>